Fluid-flow meter.



H. H. MAPELSDEN.

FLUID FLOW METER. APPLICATION FILED JULY '17, 1900.

1,104,433.- Patented July 21;.19m

Q'Velocity.

Temperature,

l n ventor' i Witnesses:

State of New York, have invented certain -nection; though its usefulnessis not 9.0.

Hesow Human. SQHENECTI'ADY, e was m as s sensennncunrc company, aconronn'lv'iofi wimiw .YonK.

meww To all whom it may concern: a

Be it known-that I, HAnoLn H. MAIfnLS- mm, a citizen of the UnitedStates, res idingj at Schenectady, county of Schenectadyd;

new and useful Improvements in gFluid- Flow Meters, of which thefollowing is a specification.

. This invention relates to apparatus for indicating and recording thequantity of applicable to the measurement ofsteemflow andwillhereinatterbe described in. that confined theretobutmay extendtothemensure- .ment of airor any other fluid.

The object ofthe invention is to simplify the structure of theinstrumentandlendfer .it possible to locate the indicating and recordingmechanism .in an engine room .or other station a,t a, distance from thesteam main, while the devices responsive to .th velocity, temperatureand .pressure of the steam are located at the main and connected;

,witht-he recording mechanism by a .iew insulated .wires of anysuitabledength. Thei velocity-responsive device illustrated is aji Pitottube connected to -a U-tube containingl mercury which acts. to cut outmore or less of; a resistance coil. The temperature-respon-Z;

sive device is aresistance coil whose resistiv- 'velocity, pressure andsuperheatof the steam.

'In the accompanying drawing, iFigure 1' shows the inventiondiagrammatically; 2 illustrates a modification 'ofthe U-tube;. and Fig.-3 is a simplified diagramfleflthe circuits.

In the steam main 1 .are.lo cated two small Pitot' tubes orfunnels 2, 3,onegfacing toward the flow and the other away ."fromit. uT-he funnelsare connected respectively with the ends of a U -shaped tube atpartlyfilledwith l mercury and containing in the'low pressure 5 eleg acoil of wire 5,.whose .terminals are led out through the .walls of thetube, one at the upper end of.tl1e-low pressure-leg and the other at apoint nearthe'bottom of the tube. The .former terminal is connected .by

-the conductor.6 with the negative line conductor'7, while the latterterminal is con nected 'by.the conductor 8. .with a solenoid 9 connected-.by the wire .10 .with :theipositive dine conductor 11.

A.metallica'esistance.coil 12 islocated in the main '1;oneterminal;beinglconnected.to

one endofthe coil .5,.and.gthe .other to a solenoid 1.3 ;in circuit,wit-li fl the positive lead 10. I

' .'A pressure-responsive. deyice, 1 preferably a .Bourdon tube .14, isin czghmiinica'tion with :themain 1,:its free en eingfmechanicallyconnected, preferably .by multiplying gearingl5, withlth switch-arm;16I.0f a rheostat x17. ilhe .arm'is connected with the @lower terminal.of -the coil 5, .while I the rheostat coils are. .connectedwith asolenoid .-18;in circuitwith thepositivez'lead 10. l .The-threesolenoids.-9, 1'31 and 18 are all in 'axialalinement, and theirl movablecores 19, 20, and 21 are all attached to. a common rod 22. lEiLQl'lsolenoid and core constitutes an .electrormotive device. A spring 23,.adjust .ablebyaneansof .a nut' 24, draws said rod downwardagainst-thedift ofthe solenoids 9 and-18. .Therodisconnected, preferablythrough .racks 25,26 ahdgear wheels 27, with a pencil or-marking device28 adapted to draw .ailine. upon .a record sheet 29, which is preferablymounted on a cylinder driven by clockwork 3.0 ,at an even rate. Thesheet is graduated to indicate steam flow of so many pounds in givenincrements of.- time.

Theoperation'is as *follows: {The instrument.isfirstadjustedwhen thereis no steam in themain 1 and the solenoids13, and 18 are out of circuittemporarily. '-.With no steamfiow.themercurywill stand at the'samezlevel inzboth legs ofthe tube 4, and the resistivity of. the 'co1l-5 will be at a maximum, soithat a current at .a constantvo1tage.of,.say,Y-11O volts will. producea certain pull in .the solenoid 9.adjusting the tension ofthe spring 23 to balance. this. pull, the pencil28 can be set at the'zero mark on the record sheet. Now letsaturatedsteam at a predetermined normal pressure, say-150 poundsgrge,beadmittedv to-the main; said steamthaving. no superheat.=|ThisIpressure 11 will tend to straighten the Bourdon tu be therebycutting out some of the rheostat coils 17 and permitting some current to'fiow,

through the solenoid 18 when its circuit is closed. This additional pullcan be counterbalanced by a further tightening of the nut 24. Finall letthe steam be superheated to some relietermined normal temperature abovet at of saturated steam at 150 pounds gage pressure. This will heat upthe coil 12 and increase its resistance, cutting down the current whichwould otherwise flow through it. Upon closing the circuit of thesolenoid 13it will exert a certain pull, but not so much as it would hadthe steam not been superheated. Adjustment for this weakened pull ismade, so that the pencil will still stand. at zero. Themain isfnowassumed to contain su erheated steam at normal' pressure but not inmotion. If then the throttle in the main be 0 ened, the velocity of themoving stream :0 steam .will affect the mercury colunmin the tube 4,causing it to rise in the right ha'nd leg and. thereby cut down theresistivity. of the coil 5'.- More current'will therefore, flow throughthe solenoid .9, whose pull is therefore increased, and the pencil'willmove down toindicate the weight of steam consumed in a- 'ventime. Solong as there is noichange. in t e pressure or the superheat, thevelocity meter will properly indicate the amount of steam used.

The more-rapid the flow of steam, the higher will be the level of themercury in the low pressure. leg of the tube 4 and the lower will be theresistivity of the coil 5. The quantity of the steam flow thusdetermines directly the amount of current impressed upon the solenoid9,.whose core will belifted to a corresponding height a ainst thetension of the spring 23, while t e pencil 28*will be flow during agiven time.-

pulled down to the proper point on the record sheet 29 to indicate andrecord the particular steam flow. This oint will vary I decreases "orincreases, and the .line drawn b the-pencil on 1 the. sheet will formagraphlc chart of the-' As is well known, the pressure difierenoef setup by'a Pitot tube bearsa certain relation to t e velocity and .to thedensity of the steam. "As pointed out above the meter is firstcalibrated for variations in velocity at. constant density and so longas this constant density 'is maintained the meter will recordcorrectly.- If. now, however, changes in.

density occur, as for example, by an 'in.'-.

crease or decrease in the superheat O1: a I change pressure or both, thedeflection off as to correctly the mercury in-the U.-tube. will not besuch indicate the flow on a' scale. orre'cord ca which is calibrated forsome, other density. It therefore, necessary to correct for suchchanges, and to automati-i cally make suchcorrections is the functionthe coil 12.

wall of the tube into themereu therein. Such. a structure is i1 ustrated1n of the pressure and temperature responsive devices. Assume forexample that there is a. change in density due to an increase inpressure. This would mean that there is a greater. weight of steamflowing. The deflection of the U-tube, however, will not be such as torecord correctly the flow at this new density and it is, therefore,necessary to correct for the same. In otherwords, for this new rate offlow at greater pressure, the meter would, were no correction made,record too little. As soon as the density increases, however, theBourdon tube 14 causes the switch arm 16'to'cut out more coils of therheostat 17. More current will then flow through the solenoid 18 andthus strengthen the pull on the rod 22 which causes the pointer toindicate greater steam flow and thus correct for the change in density.

When the steam is superheated, its weight becomes less for a givenpressure. To compensate or correct for superheat therefore, the pull ofthe coils 9, 18 must b complished b the solenoid 13 in circuit with ithan increase in temperature the resistivity of the coil 12 increases, so

as to weaken the current flowing throu h the solenoid 13, whichthereupon permits t 'e' spring 23 to exert a downward pull on the ecounterbalanced to the proper extent. This is ac-j rod and causes-thepeneil to indicate and l record a lessened weight of steam. Theinstrument thus integrates the three .'factors of velocity, pressure andtemperature, and indicates and records the result upon the properlygraduated record sheet in terms of pounds of steam used per hour, orother .selected interval of time.

In Fig. 1 the resistance coil 5 is shown as inserted into the tube 4. Inpractice, however, it is found referable to wind the 0011 around theoutsi e of the tube, and connect.

it at intervals to taps passing through the contained Fig. 2, the leg 31being the low pressure leg in this instance. It willbe observed that thethree solenoids are in parallel branch circuits and that the velocityresistance coil 5 is'in multiple-series with all three branches. Theresult of noid on the record will .not be disturbed and will dependentirely upon the control exerted by its own responsive device.

While I have shown and described solenoids as the electromotive devicesin my instrument, yet I wish it understood that other forms of suchdevices may be used if desired, and that the word solenoid inthespecification and claims is intended to cover and include such otherelectromotive devices.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof;but I desire to have it understood that the apparatus shown is onlyillustrative, and that the invention can be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is,

\ subject to changes in its condition, comprising a device responsive tothe velocity of the flowing fluid, a device responsive to the statiepressure in the main, a device responsive to the temperature of theflowing fluid, an indicating mechanism, and means whereby said mechanismcan be jointly controlled by said three devices to determine the weightof fluid flowing through the main.

2. A flow meter for elastic fluids, comprising three electro-motivedevices, a velocityresponsive device, a device responsive to staticpressures, a temperature-responsive device, suitable means whereby saidvelocity, pressure, and temperature-responsive devices respectivelycontrol said electro-motive devices, an indicator, and means wherebysaid indicator is controlled by all of said electromotive devices.

3. A fiow meter, comprising three solenoids, a velocity-responsivedevice, a pressure-responsive device, a temperature-responsive device,suitable means whereby said velocity, pressure andtemperature-responsive devices respectively control said solenoids, amovable rod common to all of said solenoids, an indicator, and 'meanswhereby the indicator is moved by the rod.

4. A flow meter, comprising three solenoids in axial alinement, amovable core for each, a common rod carrying all of said cores, anindicating and recording mechanism actuated in part by said rod, avelocity-responsive device in circuit with one solenoid,a'pressure-responsive device in circuit with another, and atemperature-responsive device in circuit with the third. 1

5. A flow meter, comprising three elec-. tromotive devices, an indicatorcommon to all, means connecting said indicator and electromotivedevices, three resistance coils respectively in circuit with saiddevices, and devices respectively responsive to the velocity andpressure of the fluid, and each controlling one of said resistancecoils, said third coil being directly influenced by the temperature ofsaid fluid.

6. A fluid flow meter,'comprising three electro-motive devices inmultiple, an indicator, means whereby said indicator is controlled byall said devices, two resistance coils respectively in series with twoof said devices, a third resistance coil in multiple-series with allthree, a velocity-responsive device controlling said latter coil, and apressure-responsive device controlling one of said other coils.

7. The combination with a steam main, of three resistance coils, onewithin said main, a velocity-responsive device and a pressureresponsivedevice respectively controlling said other coils, electromotive devicesin circuit with said coils, a common indicator,

,and means whereby the indicator is controlled by said electromotivedevlces.

8. The combination with a steam main of a device responsive to thevelocity of flow of the steam through the main, a device responsive tothe static pressure of the steam in the main, a device responsive to thetemperature of the steam, said devices being all in or adjacent to themain, :1 distant indicating mechanism comprising electro-motive meanscontrolled by each of said devices, and electric connections between thedevices and said means whereby the indicating mechanism is controlled bsaid devices and caused to indicate the weight of steam flowing throughthe main.

9. The combination with a steam main, of a Pitot tube device containingmercury, said device being connected to the main so that the velocity ofthe flowing steam causes a movement of the mercury therein, a resistancecoil adapted to have its turns short circuited by the mercury, a Bourdontube connected to the main so as to be affected by the pressure of thesteam, a rheostat controlled by said tube, a resistance coil exposed tothe heat of the steam, three solenoids respectively in circuit with saidresistances, a common core-carrying rod for said solenoids, anindicating and recording mechanism, and means whereby said rod.coiiperates with said mechanism.

10. In a fluid flow meter, the combination with three solenoids arrangedin axial alinement, of a rod carrying the cores of said solenoids, anadjustable spring connected with said rod, a rack on said rod, gearingmeshing with said rack, a second rack engaging with said gearing, andrecording mechanism coiiperating with said second rack.

11. A meter for measuring the flow of elastic fluid through a main,comprising an electrical indicating device, resistance means in circuitwith the device and adapted to vary its action, means responsive-to. thevelocity of fiow' of the fiuid through the main for varyingtheresistance, and-means responsive to changesin a physical condition ofthe fluid fiowin through the main for also varying theresistance. .v

12. A meter for measuring the flow of elastic fluid through amain,comprising an electrical indicating device,resistance.means in circuitwith said device and adapted to vary its action, an, agent located insaid main that creates a pressure difference for varying saidresistance.

vary

.'.a=13.--Ai meter-flier measuring the flow 'of elastic fluid through amain, comprising an electrical indicating device, resistance means incircuit with saidfl de vice and adapted to its action, an agentlocated'ln said mainthat creates a" pressure difference whose valuebearsadefinite relation to the rate of flow of the fluid, means responsive tochanges in the pressure difieren'ce'created by said agent for varyingsaid resistance,

-an'd further means responsive to a chan e in 'a condition of the fluidfor varying said resistance. a; l

In witness whereof, I have hereunto set my hand this 15th'day of July,1909.

. HAROLD MAPELSDEN.

Witnesses: j a i a HELEN ORLFORD.

W; G. GARTNER.

